The present invention relates to a disk player, and more particularly, to a method for restoring an unused area so as to reuse the unused area which is generated during the recording or editing of a mini disk player.
First, the unused area of the disk, generated when a conventional mini disk player edits the tracks, will be described below.
FIG. 1A shows the distribution of four tracks when the tracks are fully recorded. When the four tracks are edited, tracks 1, 3, 5 and 7 are generated as shown in FIG. 1B. Even though tracks 1, 3, 5 and 7 are erased for recording data as shown in FIG. 1C, the tracks remain as an unused area due to the small recording capacity thereof.
That is, since the unused tracks such as tracks 1, 3, 5 and 7 increase during the conventional track editing process, the amount of the recordable tracks per total number of tracks decreases.
On the other hand, the mini disk player records the data in the disk using a user table of contents (UTOC) shown in FIG. 2A. Referring to FIG. 2A, the byte position from a pointer's value P (decimal) is calculated using the following formula: EQU 76.times.4+P.times.8
Here, P-DFA represents the pointer for the start address of the defective area, P-EMPTY represents the pointer for the first empty slot on the parts table, P-FRA represents the pointer for the start address of the freely recordable area, and P-TNO n represents the pointer for the start address of track n. Start and end addresses are classified into a 14-bit cluster, a 6-bit sector and a 4-bit sound group.
Track mode represents the mode while the track is used, and LINK-P represents the byte position that gives the next part-descriptor of the same track. If the value of LINK-P is 00h, the track ends with the end address. The byte position of the next part-descriptor is calculated as 76.times.4+(LINK-P).times.8.
The pointer value of FIG. 2A should be a hexadecimal number and LINK-P of the above formula should be a decimal number. Also, the part-descriptor corresponds to the 304th to the 2351th bytes of FIG. 2A and describes the recordable part of the user area.
When the mini disk player records data on the disk, first, the value in the square bracket of P-FRA is checked for recognizing the start address of the freely recordable area using the UTOC. As an example, the value of [00] indicates 76th.times.4 byte and 77.times.4 byte. As shown in FIG. 2A, UTOC shows the pointer values only to P-TNO 255.
Even though there is recordable area after data is recorded from track 1 to track 255, the disk cannot be used for data recording since the UTOC shown in FIG. 2A provides information related with 255 tracks. Thus, one recorded track should be erased for recording data. Here, the re-recording is performed in only the empty track and cannot be performed in the tracks following the empty track. That is, all tracks should be erased for re-recording.
When the audio data is recorded in 255 tracks of disk shown in FIG. 3, that is, when only half the disk capacity is used for recording, the unused disk area is wasted since the UTOC table shown in FIG. 1B cannot provide information about the unused disk area, that is, the track cannot be allocated to the unused disk area.